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authorLuke Shumaker <lukeshu@sbcglobal.net>2016-06-01 15:59:00 -0400
committerLuke Shumaker <lukeshu@sbcglobal.net>2016-06-01 15:59:00 -0400
commit7f44fd8adbebc3ec21f3871d9ee04f6056398759 (patch)
treed18e26311cb7dc85ae4ee9fd946f2367705f48db /src/libbasic/hash-funcs.h
parent210548eeed2cca68cf62707388b8bba2eda66afb (diff)
./move.sh
Diffstat (limited to 'src/libbasic/hash-funcs.h')
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diff --git a/src/libbasic/hash-funcs.h b/src/libbasic/hash-funcs.h
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+++ b/src/libbasic/hash-funcs.h
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+#pragma once
+
+/***
+ This file is part of systemd.
+
+ Copyright 2010 Lennart Poettering
+ Copyright 2014 Michal Schmidt
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include "macro.h"
+#include "siphash24.h"
+
+typedef void (*hash_func_t)(const void *p, struct siphash *state);
+typedef int (*compare_func_t)(const void *a, const void *b);
+
+struct hash_ops {
+ hash_func_t hash;
+ compare_func_t compare;
+};
+
+void string_hash_func(const void *p, struct siphash *state);
+int string_compare_func(const void *a, const void *b) _pure_;
+extern const struct hash_ops string_hash_ops;
+
+/* This will compare the passed pointers directly, and will not
+ * dereference them. This is hence not useful for strings or
+ * suchlike. */
+void trivial_hash_func(const void *p, struct siphash *state);
+int trivial_compare_func(const void *a, const void *b) _const_;
+extern const struct hash_ops trivial_hash_ops;
+
+/* 32bit values we can always just embed in the pointer itself, but
+ * in order to support 32bit archs we need store 64bit values
+ * indirectly, since they don't fit in a pointer. */
+void uint64_hash_func(const void *p, struct siphash *state);
+int uint64_compare_func(const void *a, const void *b) _pure_;
+extern const struct hash_ops uint64_hash_ops;
+
+/* On some archs dev_t is 32bit, and on others 64bit. And sometimes
+ * it's 64bit on 32bit archs, and sometimes 32bit on 64bit archs. Yuck! */
+#if SIZEOF_DEV_T != 8
+void devt_hash_func(const void *p, struct siphash *state) _pure_;
+int devt_compare_func(const void *a, const void *b) _pure_;
+extern const struct hash_ops devt_hash_ops = {
+ .hash = devt_hash_func,
+ .compare = devt_compare_func
+};
+#else
+#define devt_hash_func uint64_hash_func
+#define devt_compare_func uint64_compare_func
+#define devt_hash_ops uint64_hash_ops
+#endif